Previously, high quality graphics were limited to long runs to reduce cost or short runs, wherein the costs were excessive. With the advent of Scotchprint.TM. graphics, production of limited quantities of high quality graphics were readily affordable. Furthermore, Scotchcal.TM. 8620 and 8640 receptor-coated films have permitted the use of such high quality graphics for limited quantity applications for rigid surfaces. These marking films comprise a vinyl film base that is top coated with a solvent thermoplastic blend of acrylic copolymer, vinyl chloride/vinyl acetate copolymer, and a plasticizer. This top coating is a non-tacky solid that is moderately flexible at room temperature. Above 70.degree. C., the thermoplastic melts and bonds onto electrostatic toners that were previously printed onto a transfer media. After cooling, the marking films can be separated from the transfer media and the toners are retained by the marking film.
Ideally, the thermoplastic layer (1) adheres well to the base film, (2) does not adhere to untoned (unimaged) areas on the transfer media, (3) does not destroy the physical properties of the base film (tensile, elongation, color, etc.), (4) bonds completely to the toners, permitting removal of toner from the transfer media and not permitting toner removal during normal application, (5) is not tacky during normal use, and (6) is compatible with additional operations, such as clear coating or premasking.
However, continuously flexed surfaces, such as the transports and vehicles with plasticized polyvinyl chloride coated fabric sides prevalent in a large portion of the world have proven to be a problem for the receptor-coated films. Typically, the plasticized polyvinyl chloride coated fabric is a thermoplastic material flexed, rolled, flapped, and cold-flexed numerous times during the lifetime of the siding. Hence, any graphic image adhered or otherwise attached to such a siding must be capable of withstanding identical stresses without failure.